﻿608 
  I'ROCEEDiyas 
  OF 
  Till-: 
  X.IT/OXAL 
  MiSEVM. 
  

  

  il)piue 
  Dieaeidae 
  for 
  instance; 
  most 
  of 
  the 
  larger 
  islands 
  liave 
  a 
  repre 
  

   sentative 
  of 
  the 
  J), 
  dorsale 
  type, 
  and 
  one 
  of 
  the 
  D. 
  hacmatostk'tnm 
  

   type. 
  The 
  prevailiu,<>- 
  colors 
  of 
  tlie 
  former 
  group 
  of 
  si)ecies 
  are 
  shite 
  

   blue, 
  orange, 
  and 
  scarlet; 
  those 
  of 
  the 
  latter 
  black, 
  white, 
  and 
  red, 
  or 
  

   scarlet, 
  yet 
  nothing 
  is 
  commoner 
  than 
  to 
  hnd 
  representatives 
  of 
  the 
  

   two 
  groups 
  feeding 
  side 
  by 
  side 
  from 
  the 
  same 
  tlowers. 
  

  

  With 
  six 
  rei)reseutatives 
  in 
  Luzon, 
  five 
  in 
  8am<ir, 
  four 
  in 
  Leyte, 
  

   three 
  each 
  in 
  Mindoro, 
  Masbate, 
  Negros, 
  Mindanao, 
  Basilan, 
  and 
  Sulu, 
  

   and 
  two 
  in 
  Siquijor, 
  Cebu, 
  Gnimaras, 
  Panay, 
  Sibuyan, 
  Catanduanes, 
  

   Dinagat, 
  and 
  Tawi 
  Tawi, 
  the 
  genus 
  Dicaeum 
  would 
  be 
  somewhat 
  dis- 
  

   figured 
  if 
  Steere's 
  law 
  were 
  to 
  be 
  strictly 
  enforced 
  upon 
  it. 
  

  

  Numerous 
  other 
  instances 
  of 
  the 
  singular 
  conclusions 
  into 
  which 
  this 
  

   law 
  would 
  lead 
  us 
  might 
  be 
  given, 
  but 
  I 
  think 
  that 
  those 
  already 
  men- 
  

   tioned 
  will 
  suftice. 
  

  

  In 
  fornuilating 
  his 
  law, 
  Steere 
  offers 
  the 
  following 
  as 
  an 
  alternative 
  

   for 
  the 
  statement 
  of 
  it 
  already 
  given 
  : 
  "No 
  two 
  species 
  near 
  enough 
  

   alike 
  structurally 
  to 
  be 
  adapted 
  to 
  the 
  same 
  conditions 
  will 
  occupy 
  the 
  

   same 
  area." 
  This 
  statement 
  seems 
  to 
  me 
  to 
  be 
  self-contradictory. 
  

   Individuals 
  of 
  any 
  given 
  species 
  are 
  certainly 
  adapted 
  structurally 
  to 
  

   about 
  the 
  same 
  conditions, 
  yet 
  they 
  manage 
  to 
  exist 
  together. 
  If 
  two 
  

   species 
  structurally 
  adapted 
  to 
  the 
  same 
  conditions 
  were 
  brought 
  into 
  

   competition 
  in 
  a 
  given 
  area, 
  each 
  would 
  continue 
  to 
  exist 
  in 
  the 
  area 
  in 
  

   question 
  in 
  numbers 
  proportionate 
  to 
  the 
  number 
  of 
  each 
  at 
  the 
  time 
  

   competition 
  began. 
  

  

  I 
  find 
  no 
  satisfactory 
  line 
  of 
  argument 
  in 
  Steere's 
  paper 
  leading 
  up 
  

   to 
  his 
  conclusion 
  that 
  isolation 
  is 
  the 
  first 
  and 
  necessary 
  step 
  in 
  the 
  

   formation 
  of 
  species. 
  This 
  conclusion 
  necessarily 
  raises 
  the 
  whole 
  

   question 
  of 
  the 
  way 
  in 
  which 
  environment 
  acts. 
  No 
  one 
  will 
  deny 
  that 
  

   it 
  has 
  its 
  effect, 
  but 
  does 
  it 
  act 
  directly, 
  stimulating 
  the 
  production 
  of 
  

   variations, 
  or 
  indirectly 
  by 
  favoring 
  some 
  of 
  the 
  variations 
  spontane- 
  

   ously 
  presented 
  to 
  it? 
  

  

  Manifestly 
  there 
  can 
  be 
  no 
  progressive 
  development 
  without 
  varia- 
  

   tion, 
  and 
  in 
  saying 
  that 
  isolation 
  is 
  the 
  first 
  and 
  necessary 
  step 
  in 
  

   species 
  formation 
  Steere 
  commits 
  himself 
  to 
  the 
  former 
  view. 
  His 
  

   position 
  does 
  not 
  differ 
  essentially 
  from 
  that 
  of 
  Moritz 
  Wagner 
  and 
  his 
  

   followers, 
  nor 
  can 
  I 
  see 
  that 
  he 
  has 
  added 
  anything 
  new 
  to 
  the 
  evidence 
  

   bearing 
  on 
  the 
  subject. 
  The 
  mere 
  fact 
  that 
  there 
  are 
  numerous 
  geo- 
  

   graphical 
  races 
  of 
  birds 
  in 
  the 
  Philippines 
  does 
  not 
  atitbrd 
  an 
  explana- 
  

   tion 
  of 
  the 
  part 
  played 
  by 
  geographical 
  isolation 
  in 
  producing 
  them. 
  

  

  FACTOKS 
  IN 
  THE 
  ORIGIN 
  AND 
  DISTRIBUTION 
  OF 
  THE 
  GENERA 
  AND 
  

   SPECIES 
  OF 
  RESIDENT 
  PHILIPPINE 
  LAND 
  BIRDS. 
  

  

  I 
  have 
  thought 
  it 
  worth 
  while 
  to 
  examine 
  with 
  a 
  good 
  deal 
  of 
  care 
  

   the 
  facts 
  brought 
  out 
  in 
  Tables 
  A 
  and 
  B, 
  in 
  order 
  to 
  ascertain 
  whether 
  

   they 
  afford 
  foundation 
  for 
  any 
  general 
  principles 
  of 
  species 
  formation 
  

   and 
  distribution, 
  and 
  have 
  first 
  endeavored 
  to 
  ascertain 
  whether 
  there 
  

  

  